1. Field of the Invention
The present invention relates to optics. More specifically, the present invention relates to systems and methods for using laser transmitters and receivers for target detection.
2. Description of the Related Art
For military and other applications, there is a need for a system or method for detecting proximity to a target, surface or other object. Many techniques are known in the art for effecting proximity detection using a variety of technologies. For example, for highly demanding military applications, lasers are currently being used for many range finding and proximity detection applications. Lasers are preferred because the coherency and brightness of laser beams allow for long range and high detection accuracy compared to alternative technologies such as radio frequency and infrared based systems.
For both range finding and proximity detection applications, a beam from a laser transmitter is directed to a target and a reflection thereof is detected by a receiver. For range finding applications, the round trip time of a pulse is measured to determine target range. For proximity detection applications, a more simple detection of a return beam is effective to signal target proximity.
Unfortunately, the signal noise ratio (SNR) of current active optical target detectors (AOTDs) or ‘optical fuses’ is low. This is particularly problematic with respect to the effect of noise caused by solar energy. The low SNR affects the range, sensitivity and size of the detector when used in a missile application by way of example.
Hence, a need exists in the art for an improved system or method for detecting proximity using a laser transmission and reception scheme.